# Molality question

1. Feb 6, 2005

### bomba923

How do I find the molality of an aqueous solution containing 1g/L of a certain protein with molar mass 9.0 x 10^4 g/mol if the density of the solution is 1g/(cm^3)??

2. Feb 6, 2005

### chem_tr

Molality is expressed with mole of the solute in one kilogram of solution. Try this approach first.

3. Feb 6, 2005

### bomba923

My book says molality is moles of solute over kilograms solvent.

My question/problem is how to find the kilograms of solvent :surprised

4. Feb 6, 2005

### dextercioby

U needn't.Use what Chem_Tr told u and a bit of logics.Just to get u started

1g protein--------------------->1L solution
1g solution--------------------->1 cc solution

Question:
1g protein--------------------->x Kg solution...

Why didn't i pick "g solution" in the last line??Because u need to find moles protein/Kg solution...

Daniel.

5. Feb 7, 2005

### Gokul43201

Staff Emeritus
You may assume that adding a gram of protein to a liter of water does not change its volume (or the density).

6. Feb 7, 2005

### bomba923

In that case...yes!--I can find it